I have been exploring the scientific and philosophical concept of “emergence” (starting <here>). Summarizing my previous entries in a single sentence: my contention is that when you really analyze what emergence means when it is used as an explanation for consciousness, it is actually just another word for consciousness, and thus explains nothing.
Previously
we discussed the concepts of “weak emergence” and “strong emergence”. “Weak emergence” refers to emergent
properties that are, at least in principle, explainable by the underlying
physical properties. In my opinion, weak
emergence is ubiquitous, but has nothing to do with human consciousness. In “strong emergence”, the connection
between the higher-level events and the underlying physics becomes strained and
broken in some manner. I
previously made the claim that it is very misleading to use the terms “weak
emergence” and “strong emergence” because it makes it sound like the two terms
are related, whereas, in reality, the two terms have almost nothing in
common. I suggested that a better term
for “strong emergence” was “beyond physics” (i.e. “metaphysics”) or, even more
simply, “consciousness.”
I said
there were two features that tend to get combined under the heading of “strong
emergence”, and that these two features are also so different from one another
that they should each be given a separate descriptive term – i.e. they
shouldn’t be combined under a single term.
The first feature of strong emergence was that the emergent
property cannot, even in principle, be explained by the underlying
physics of the situation. You can read that entry here. In today's entry, it is
now time to address the second feature of strong emergence.
The
second major feature often lumped under the term “strong emergence” is the idea
that, in some manner (often undefined) the emergent property can exert a
top-down effect on the underlying physics or the underlying fundamental
particles. This is often referred to as
“downward causation.”[1]
It’s hard
to come up with an example of downward causation, so I’ll start with something
hypothetical. Let’s say that the flow of
water molecules could be described as an emergent property called “river”, and
then “river”, by virtue of where it decides to flow, exerted an influence on
the water molecules to make the water molecules move where the river “wanted” them
go. That would be an example of
“downward causation”. The emergent
property of “river” would be obeying its own laws that are outside, or in
addition to, the fundamental laws that govern the interactions of the water
molecules. In this case, if you applied
the fundamental laws to all of your water molecules, you would find that they
are not moving exactly as you predict because the river is exerting an
outside influence on one or more of the water molecules (that influence is, in
this hypothetical example, not itself included in the fundamental physics of
the situation). Now, that is not
how it works with water molecules and rivers. Rivers are defined by the collection and
interaction of the water molecules that make it up, as well as the environment
surrounding the water molecules (i.e. the molecules that make up the river bank
and river bed). There is no separate,
distinct “intentional river flow” that exists apart from the fundamental
principles of physics for the entire system.
Thus, in reality, river flow is actually an example of weak emergence,
not strong emergence.
You may
wonder “well, what example could there possibly be of strong emergence?” That is a valid question! Frequently, people devolve to using
consciousness as the primary (or only?) example of strong emergence, something
I find pretty circular.
Sometimes
people come up with examples of “emergence”, where, if you listen closely, you
will realize that there is a human involved in their example somewhere
along the way. A conscious
human. Let me give you a very common
example of this: traffic flow as an
emergent property of multiple cars driving on a road. Traffic patterns arise (emerge) from these
cars as they drive, patterns such as the stop-and-go waves that we get stuck in
on our way to work. You can’t just
examine a single car driving along and predict the various kinds of traffic patterns
that will emerge from a whole group of cars on the road. Thus, traffic patterns are considered an
emergent property. Philosophers will
then say “just like complex traffic patterns emerge from a group of single cars
driving on the road, so analogously, consciousness could arise from a group of
neurons acting in a complex network.”
There are two important problems with this. First, traffic patterns are weak
emergence and, in fact, can typically be simulated with software. The comparison between traffic and
consciousness is based on an implied link between the weak emergence of
traffic patterns and the strong emergence of consciousness. What is that link? They both have the word “emergent” in them –
but otherwise they are unrelated concepts! That is why I think it is wrong to use the
term “strong emergence”, as I pointed out in my previous entry on this topic
<here>.
However,
there is another funny thing about calling traffic an emergent property and
then using it as an analogy to explain how consciousness arises from the brain. Cars don’t do anything unless they are driven
– driven by a human being – a conscious human being. Cars don’t make decisions; the human drivers
do. Presumably, those humans utilize
their conscious brain to make those decisions and initiate the actions
they make as drivers. This is like
defining a word by using the same word in the definition. In some real way, traffic flow is just the
action of a lot of conscious human drivers making their conscious
decisions. To then describe traffic flow
as an emergent property and therefore analogous to consciousness seems very
circular to me.
Sometimes
examples of strong emergence are open systems rather than closed systems. Open systems are those where there are
“outside influences” on how the system behaves.
These outside influences then can become the top-down influence of
strong emergence. For example, life
itself is sometimes put forward as an example of strong emergence, because it
emerges from the underlying biochemical activity, but life also seems to exert a
top-down influence on what the living thing does. Living things do purposeful activities but
the underlying chemicals and reactions do not have anything like “purpose” as
part of their properties. But living
things are not closed systems. They must
constantly ingest some kind of energy to keep going and stay living. They are also living within an external
environment. To me, this seems analogous
to the “water and river” example I gave earlier. The banks of the river are the environment
that the water finds itself in, and the banks exert an influence on where the
water molecules go. But, if we include
the river bed and river banks into our fundamental system, then there is no
emergent “top-down” influence. I feel
that claiming something has an emergent, top-down influence when the system is
open is suspect. It seems that those
outside influences need to be brought within the explanation of the system in
order to determine if there is strong emergence. I’m sure there is plenty of debate on that
particular point.
In the
last entry, I argued that the first aspect of strong emergence, the aspect of a
disconnect between the “emergent” property and the underlying physics, was
typically just another word for consciousness.
Or, I suggested the word “metaphysics” be used in this case. So, what word should be used to describe this
second aspect of strong emergence – the aspect of downward causation? In my opinion, we already have a word for
that: “will”. Maybe more commonly in philosophy, the term
“agency” is used. But, it seems to me
that downward causation is just describing the higher-level system exerting its
“will” on the lower-level system.
For the
purposes of this discussion, I am not claiming any particular freedom in the
term “will” in this case – i.e. I’m not claiming that this is necessarily “free
will”. If you are a determinist, then
maybe you would call it “determined will”, I don’t know. In fact, even though I am a strong proponent
of free will itself, I don’t think that downward causation always fits under
the category of “free” will. Just “will”
– or “agency” – or maybe even “purpose”.
I think that life is actually an example of this concept. Living things exhibit a purpose. Thus, I would consider life to be a strongly
emergent property, except that I would never use the confusing term “strong
emergence.”
So, to
summarize, I think that the terms “weak emergence” and “strong emergence” are
very misleading. I propose three terms
to describe these ideas. First, the term
“emergence” would be retained to describe those things that would be typically
categorized under “weak emergence.” Then
I would use the term “consciousness” for those things that have the first
aspect of strong emergence – that they somehow depart from (or modify) the laws
of physics. And finally, I would use the
term “will” or “agency” for those things that exert downward causation that is
independent of the underlying physics. I
have previously introduced my thinking about how I see consciousness and agency
as being connected in human behavior in my discussion on the soul <here>. I think consciousness and will are related,
but are not the same thing.
Now,
given this background, we will go back to the discussion on water molecules and
liquidity. Next time.
[1] Is
there some bigotry on our part when we place particle physics always at the “bottom”
and things like life and consciousness at the “top”? Why should increasing complexity be seen as
“higher than” or “above” things that are less complex? And are quarks and gluons actually less
complex than humans? If so, then why is
quantum mechanics so difficult for humans to understand?
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